First: make sure your head unit can handle running both the speaker level outs and the RCA outs from the rear. Not sure, and my manual is not near by, but I think my Clarion CMD3 does not allow you to use speaker outs and RCA outs at the same time.

Second: Why are you running your 2 tower speakers bridged (and by bridged you mean the pos is on channel 1 and neg is coming from channel 2).You are loosing the left and right by doing this. You have a 2 channel amp, run one speaker to each channel. If you think you are getting twice the power bridged, you are, but it is split between two speakers, same as running them straight.

T running your towers bridges is fine if your amp can handle the lower ohm load. This will actually give your tower speakers more power. You don't need stereo sound when the speakers are 4 feet apart and your listening to them from 70' back

First: my mystake, what I was thinking of was not to run a amp from speaker level inputs and RCA inputs at the same time.

Second: Running bridged does give you twice the power but you are spliting that power between two speakers, the same as if you were running them each from their own channel. As well, you will be running your amp at 2 ohms load bridged, and 4 ohms straight which will create alot less heat and minimize chance of overheating. And you will have stereo for those in the boat by using their own channels.

T I agree with everything you say except it will give your speakers DOUBLE THE POWER. For example. You have an amp that does 150x2 RMS @ 4 ohms. Bridge that amp and it will be giving you 600x1 RMS @2 ohms. That will be giving each speaker 300watss RMS. If its a decent amp and rated to be 2 ohm stable, it should have no problem with overheating. He is using a seperate 2 channel amp so there is no reason why he needs to worry about supply stereo sound to the boat.

I will check the headunit to see if I can run an amp and the speakers to the unit. Thanks guys. I didn't know to check that. I am runing the tower amp bridged because I thought it would make my tower speakers a little louder.

No, your amp will not handle a bridged 2ohm load (thats what two 4ohm spearkers in parallel will pull). Look at the the Specifications - Rated power output (2 ohms)section there is no bridged choice like listed under the 4ohms. If your amp was safe bridged at 2ohms it would list a bridged rating. Does this make sense?

If you are going to run it bridged, it is only rated for 4 ohms bridged.

I'm using my old MB Discuss speakers on the tower -- going to replace though in the winter. Just replaced 6 Alpine speakers in the boat with 6 Polk DB650's. The sub is a 12inch Crossfire (I think) ... getting a custom box built for it now, painted yellow to match the boat. I'll post pics when it's all done. Should be finished next week.

Ronia - the picture at the bottom of the page is showing two 4 ohm speakers in parallel. They are going to the same channel and you can see it is showing a combined load of 2 ohms. That is not a bridged diagram. A bridged diagram would have 2 channels showing (ie 2 positive and 2 negative hook ups and you would use 1 positive from one channel and the negative from the other channel).